feat(v2.3.0): self-healing fallback system — auto-recovery from Cloudflare blocks

pipe.js now tries 3 methods in order with automatic fallback:
1. Direct — mirror rotation (.ru → .to → .bz → .tv) with browser headers
2. ScraperAPI — free proxy (1K req/mo, no CC required)
3. FlareSolverr — self-hosted browser proxy (solves Cloudflare Turnstile)

When one method fails (403/timeout), the next is tried automatically.
Zero-config: works without any env vars. Add SCRAPER_API_KEY or
FLARESOLVERR_URL for Cloudflare bypass.

New endpoint: /api/pipe-health — tests all configured methods,
reports latency and working/failed status, recommends preferred method.

Files changed:
- src/helpers/pipe.js — methodDirect(), methodScraperAPI(), methodFlareSolverr(), pipeHealthCheck()
- src/routes/apiRoutes.js — added /api/pipe-health endpoint
- .env.example — documented SCRAPER_API_KEY, FLARESOLVERR_URL

Version bumped to 2.3.0 across package.json, server.js, /api/health,
/api/openapi, public/openapi.json. CHANGELOG updated.

server.js

@@ -301,7 +301,7 @@ app.use((req, res) => {
 
 if (!process.env.VERCEL) {
   app.listen(PORT, () => {
-    console.log(`[${new Date().toISOString()}] MiruroAPI v2.2.0 listening at ${PORT}`);
+    console.log(`[${new Date().toISOString()}] MiruroAPI v2.3.0 listening at ${PORT}`);
   });
 }